Docker image does not autobuild

[jakkn]

Problem Description

Due to https://www.docker.com/blog/changes-to-docker-hub-autobuilds/ the autobuild of the docker image stopped working. The consequence is that the image must be built manually, and is likely to fall behind and stay outdated for longer periods of time.

Suggested Solution

1. Use github actions to build and publish the image.
2. Trigger the build on upstream changes.